AGRIC^DEPT, 


**^ 


AGRfiX 

LIBRARY 


AGRICULTURAL 
LIBRARY, 

UNIVERSITY 
CALIFORNIA. 


U.  S.  DEPARTMENT  OF  AGRICULTURE. 

-     DIVISION  OF  VEGETABLE  PATHOLOGY. 


XPERIMENTS  IN  PREVENTING  LEAF  DISEASES  OF  NURSERY  STOCK 
IN  WESTERN  NEW  YORK,  ' 

BY   D.   G.    FAIECHILD. 


REPRINTED  FIIOM  TTTE  JOURNAL  OF  MYCOLOGY,  VOL.  7,  No.  3,  BY  AUTHORITY 
OK  THK  SECRETARY  OF  AGRICULTURE. 


;»»>» 
As**-? 


. 


U.  S.   DEPARTMENT  OF  AGRICULTURE. 

DIVISION  OF  VEGETABLE  PATHOLOGY. 


EXPERIMENTS  IN  PREVENTING  LEAF  DISEASES  OF  NURSERY  STOCK 
IN  WESTERN  NEW  YORK, 

BY   D.   G.   FAIKOHILD. 


REPRINTED  FROM  THE  JOURNAL  OF  MYCOLOGY,  VOL.  7,  No.  3,  BY  AUTHORITY 
OF  THE  SECRETARY  OF  AGRICULTURE. 


* 

240 


EXPERIMENTS    IN    PREVENTING    LEAF    DISEASES    OF    NURSERY 
STOCK  IN  WESTERN    NEW   YORK. 

By  D.  G.  FAIRCHILD. 

[Plates  XXI-XXIX.] 

It  is  the  intention  to  give  in  the  following  paper  a  brief  account  of 
experiments  made  during  the  seasons  of  1891  and  18913  with  a  view  of 
preventing  the  various  leaf  diseases  of  nursery  stock.  These  experi- 
ments were  carried  on  at  Geneva,  N.  Y.,  one  of  the  largest  nursery 
centers  east  of  the  Mississippi.  The  kindness  of  Dr.  Collier,  di- 
rector of  the  New  York  State  Agricultural  Experiment  Station,  made 
it  possible  for  the  wrork  to  be  done  upon  the  station  grounds,  where 
proximity  to  the  laboratories  and  assistance  from  the  station  staff 
greatly  facilitated  the  work. 

To  bring  together  in  one  article  the  results  of  the  experiments,  it  will 
be  necessary  to  repeat  in  part  matter  that  has  previously  been  pub- 
lished.* 

The  original  object  of  the  experiments  conducted  at  Geneva  was  to 
throw  light  upon  the  following  questions: 

(1)  Can  the  leaf-blight  of  pear,  cherry,  plum,  and  quince  stocks  and 
the  powdery  mildew  of  the  apple  be  prevented  by  the  use  of  Bordeaux 
mixture  or  ammoniacal  solution  of  copper  carbonate? 

(2)  What  effect  is  produced  upon  the  growth  of  nursery  stock,  budded 
and  not  budded,  by  repeated  treatments  with  Bordeaux  mixture  and 
ammoniacal  solution? 

(3)  What  effect,  if  any,  has  the  variety  of  stock  upon  the  scion  or 
"bud"  with  respect  to  its  resistance  to  leaf-blight? 

While  the  experiments  have  thrown  considerable  light  upon  the 
first  and  second  questions,  the  nursery  was  not  extensive  enough  nor 
the  soil  uniform  t  enough  to  admit  of  any  but  general  conclusions  being 
drawn  as  to  the  third  question.  Further,  the  experiment  was  begun 
so  late  in  the  season  that  it  was  not  possible  to  secure  stocks  of  uniform 
size,  and  it  is  doubtful  if  any  experiments,  unless  made  upon  uniform 
soil,  with  stocks  grown  from  cuttings,  will  settle  in  a  satisfactory 
manner  a  phase  of  this  problem  in  which  there  are  so  many  variable 
factors. 

The  various  leaf  diseases  will  now  be  discussed,  together  with  the 
results  of  the  experiments  made  for  preventing  them.  The  numerous 

"Annual  Report  of  -ttie  &eretaVy.o£  Ap'/cujture  for  1891,  p.  368.  Bull.  No.  3,  Div.  of 
Veg.  Pathology,  pp.  57-60.  Ten'th'  Itnn  .'.Report  N.  Y.  Agrl.  Expt.  Sta.,  1892,  pp. 

1  79-18  1.  /,::•*;  %:;Y*:     *      ' 

t  As  the  expefinJcfnts  f/fagreSsefl 


-.pJafrily  evident  that  a  strip  30  feet  or  so 
•wide,  at  the  west  end  of  the  block,  had  at  some  previous  time  received  fertilizers, 
which  rendered  it  eminently  suited  to  the  needs  of  pear  stocks.  As  no  accnrato 
record  of  this  portion  of  the  farm  seems  to  have  been  kept,  it  was  impossible  to, 
ascertain  what  fertilizers  had  been  used  upon  the  strip. 


241 

• 

details,  of  interest  only  to  those  who  are  pursuing  similar  studies,  are 
given  in.  small  type  at  the  close  of  the  article. 

PEAR  LEAF-BLIGHT  (Entomosporium  maculatum  Lev.). 

This  disease  is  perhaps  the  greatest  obstacle  to  the  profitable  pro 
duction  of  pear  stocks.  The  principal  injury  is  caused  by  a  premature 
defoliation  of  the  seedlings.  When  such  defoliation  takes  place  early 
in  the  season,  as  is  quite  commonly  the  case,  the  young  seedlings  are 
forced  to  form  a  new  set  of  leaves,  presumably  at  great  expense  to  the 
reserve  material  stored  for  use  the  coming  spring.  Often  this  forma- 
tion of  new  leaves  is  repeated  two  or  three  times,  the  seedling  finally 
becoming  too  exhausted  to  continue  the  struggle.  If  the  following 
winter  be  survived,  enough  growth  may  be  made  to  render  budding 
possible. 

Although  the  disease  is  very  abundant  on  bearing  trees  further  south, 
it  seems  to  be  confined  in  western  New  York,  at  least  in  its  severe 
attacks,  to  one,  two,  and  three  year  old  seedlings,  occasionally  defoli- 
ating a  budded  stock  of  some  susceptible  variety  like  the  Flemish 
Beauty.  All  ordinary  budded  stocks  are  commonly  immune  from  the 
disease,  although  the  stocks  into  which  the  buds  are  inserted  may 
have  been  diseased  before  being  budded.*  So  far  as  the  author's  observa- 
tions go  the  fungus  causing  the  disease  does  not  attack  the  seeds  of 
the  pear  or  the  cotyledons  of  the  young  seedlings  until  two  weeks  after 
the  appearance  of  the  latter  above  the  surface  of  the  soil.  Early  in  the 
season  it  attacks  only  the  foliage,  but  later,  as  the  defoliation  continues, 
it  is  found  on  the  succulent  growing  tip  of  the  stem.  For  3  or  4  inches 
from  the  terminal  bud  the  bark  is  covered  with  small,  sunken  spots, 
bearing  in  their  centers  the  mature  fruiting  bodies  of  the  fungus,  this 
condition  first  becoming  noticeable  about  the  middle  of  August.  As 
first  pointed  out  by  Sorauer,f  it  is  in  these  sunken  spots  that  the 
parasite  passes  the  winter.  In  America  the  parasite  lives  from 
year  to  year,  as  it  does  in  Germany,  upon  the  bark  of  the  grow- 
ing seedling  and  infects  the  young  leaves  upon  their  first  appearance 
in  the  spring.  On  May  20,  before  the  foliage  of  last  season's  un- 
budded  stocks  was  two-thirds  grown,  mature  pustules  were  found 
upon  the  young  leaves  in  immediate  proximity  to  these  spots  upon  the 
twigs.  A  microscopic  examination  of  the  spots  revealed  the  parasite 
in  an  active  condition.  There  is  little  doubt  that  the  infected  twigs 


*  The  terms  "seedlings"  and  "stocks"  are  here  employed  as  in  common  use  among 
nurserymen.  A  seedling  hi  nursery  parlance  means  a  plant  grown  from  seed  before 
it  is  transplanted  into  the  nursery  row,  while  the  term  stock  is  used  to  designate  the 
seedling  after  transplanting  either  before  or  after  budding.  Whenever  I  have  referred 
to  stocks  which  have  been  budded  1  have  used  the  terms  "budded  stocks"  or  "buds." 

\Soraner,  P.  Haudb.  d.  Pflanzenkraiikheiten.  Zweitc  Aufl.,  1886,  vol.  n,  p.  373. 
Momitschr.  d.  Ver.  ztir  Boturd.d.  Gartenb.  Kgl.  preuss.  St.,  Jan.  1878.  (Cited  by 
Frank,  Krankh.  d.  Ffl.,  1880,  p.  590.; 


^374384 


242 

are  the  principal  means  by  which  the  fungus  is  carried  through  the 
winter  and  the  presence  of  an  ascigerous  form,  described  by  Sorauer, 
seems  almost  unnecessary  to  a  niaiiiteiiance  of  the  disease  in  a  region 
once  infested. 

The  practice  of  allowing  stocks  to  remain  in  the  nursery  rows  when 
leaf-blight  has  affected  them  so  severely  as  to  render  them  unburi- 
able, seems  unwise  when  considered  from  a  hygienic  standpoint. 
Such  stocks  are  almost  sure  to  harbor  the  parasite  in  its  winter  form 
upon  their  slender  branches,  which  are  lacking  in  vigor.  It  is  from 
these  stocks  that  the  disease  apparently  spreads  to  other  plantings  of 
seedlings  in  the  vicinity  and  to  such  budded  stocks  as  are  susceptible, 
it  would  seem  advisable,  therefore,  that  when  leaf-blight  causes  a  large 
number  of  failures  in  the  seed  bed,  the  diseased  seedlings  should  be 
headed  back  to  within  1  or  2  inches  of  the  ground  and  all  side  shoots 
likely  to  harbor  the  parasite  removed.  Such  procedure  would  un- 
doubtedly decrease  the  liability  to  so  early  an  attack  of  the  disease 
and  enable  growth  to  be  made  before  the  malady  had  time  to  spread 
from  infected  localities.  The  same  immunity  as  that  shown  by  rap- 
idly growing  "buds"  may  prove  here  a  valuable  factor.  It  has  been 
objected,  however,  that  the  simultaneous  appearance  of  several  shoots 
from  the  headed  back  seedling  would  prevent,  or  at  least  materially 
hinder  the  budders  in  their  work  the  following  fall.  This  obstacle 
could  be  overcome  by  the  early  removal  of  all  but  one  shoot.  It  seems 
to  me  that  this  method  of  eradicating  the  disease  is  sufficiently  prom- 
ising to  warrant  a  thorough  test.  The  matter  of  protecting  seedlings 
by  wind-breaks  has  not  been  thoroughly  tested  to  my  knowledge,  and 
from  observation  on  the  spread  of  the  disease  I  am  inclined  to  believe 
it  is  worthy  a  systematic  trial.  The  freedom  from  leaf  blight,  which 
isolated  blocks  of  pear  seedlings  often  show,  tends  to  confirm  the  ob- 
servation that  the  malady  travels  quite  slowly  from  seedling  to  seed- 
ling. In  an  experimental  block  of  seedlings  mentioned  below  it 
required  nearly  two  months  for  the  disease  to  travel  from  the  east  to 
the  west  end,  a  distance  of  150  feet. 

,  Two  quite  distinct  experiments  were  made  with  a  view  of  preventing 
this  disease,  one  inaugurated  in  1891  to  test  the  effect  of  fungicides 
upon  stocks,  and  the  other  carried  on  during  the  season  of  1892  with 
seedlings  in  the  seed  bed.  The  results  of  only  the  former  experiments 
are  recorded  here  and  an  account  of  the  latter  is  reserved  for  future 
publication. 

EXPERIMENTS   WITH    STOCKS. 

These 'experiments  were  inaugurated  in  the  spring  of  1891  and  con- 
tinued until  the  fall  of  1892.  The  stocks  planted  in  1891  were  sprayed 
both  seasons,  the  design  being  to  ascertain  the  effects  of  two  consecu- 
tive years.  The  results  are  here  presented  briefly  and  the  minor  details 
are  to  be  found  at  the  close  of  the  article. 


243 

All  the  stocks  were  sprayed  on  tlie  same  dates;  in  1891  on  May  21, 
.Tune  3  and  24,  July  9  and  24,  and  August  8  and  28.  One-half  the 
stocks  were  treated  seven  times,  on  the  dates  just  indicated,  and  one- 
half  only  three  times,  on  the  first  three  dates  named.  In  1892  the  dates 
of  treatment  were  May  26-27,  June  15-16,  June  23,  July  6-7  and  21, 
and  August  5.  One-half  were  sprayed  five  times,  on  the  first  five  dates 
mentioned,  the  other  half  six  times  as  just  indicated.  The  only  fungi- 
cides used  were  Bordeaux  mixture  and  ammoniacal  solution.  In  1891 
both  preparations  were  of  essentially  standard  strength,  but  in  1892 
the  Bordeaux  mixture  was  reduced  to  the  60-gallon  formula,  as  ex- 
plained on  a  subsequent  page  (p.  262). 

FRENCH  PEAR  STOCKS. 

1891.— Four  rows  (1,922  stocks),  of  which  1,462  were  treated  and  460 
left  untreated.  One-half  the  treated  stocks  were  sprayed  with  ammoni- 
acal solution,  the  other  half  with  Bordeaux,  at  the  dates  above  indicated. 
Although  the  disease  was  not  so  abundant  in  1891  as  in  1892,  the  con- 
trast between  treated  and  untreated  was  striking.  Seven  treatments 
with  Bordeaux  proved  efficacious,  while  neither  three  treatments  with 
Bordeaux  nor  seven  with  ammoniacal  solution  showed  as  good  results, 
and  three  treatments  with  ammoniacal  solution  were  without  apparent 
effect.  On  October  9  a  count  of  those  stocks  forced  by  the  premature 
fall  of  the  foliage  to  put  forth  new  leaves  gave  the  following  figures: 

TABLE  1. — Showing  number  of  French  stocks  forced  to  put  out  ueiv  leaves. 


Number  and  treatment  of  stocks. 

Total  re- 
leaved. 

Per  cent  re- 
leaved. 

388  stocks  treated  7  times  with  Bordeaux    

4 

1.0 

55 

16  4 

50 

13.8 

357  stocks  treated  3  times  with  ammoniacal  solution  

161 

45.0 

97 

21.0 

1892. — The  same  rows  of  stocks  as  were  employed  in  1891  were  treated 
in  1892,  but  one-half  of  them  had  been  budded  the  fall  previous,  as  sub- 
sequently described  on  pp.  258,  2G1.  The  other  half  was  purposely  left 
unbudded  to  furnish  a  means  of  testing  the  fungicides.  The  treatments 
were  made  on  dates  given  above,  using  the  formula  mentioned  on  p. 
202.  During  the  course  of  the  season  little  difference  between  treated 
and  untreated  budded  stocks  was  noticeable,  as  none  but  the  Flemish 
Beauty  were  subject  to  the  disease.  At  the  close  of  the  season,  how- 
ever, the  foliage  on  treated  Flemish  Beauty  was  much  superior  to  that 
on  untreated.  Bordeaux  proved  superior  to  ammoniacal  solution  and 
entirely  efficacious. 

The  greatest  contrast  in  the  experiment  was  between  the  treated  and 
untreated  stocks  which  had  not  been  budded.  The  susceptibility  of 
these  unbudded  seedlings  afforded  an  excellent  opportunity  to  test  the 


244 

efficacy  of  the  fungicides,  and  the  results  fully  warrant  the  extended 
use  of  Bordeaux  mixture  upon  such  stocks.  As  early  as  June  134 
the  difference  between  treated  and  untreated  sections  was  visible,  75 
per  cent  of  the  foliage  of  the  untreated  being  diseased,  while  the  sec- 
tions sprayed  with  Bordeaux  mixture  remained  healthy.  Plates  xxi 
and  xxii  show  fairly  well  the  contrast  as  it  appeared  on  October  11, 
the  two  rows  standing  only  3 £  feet  apart.  The  difference  consisted  not 
only  in  the  presence  of  foliage  on  the  treated  and  its  absence  on  the  un- 
treated, but  in  an  increased  growth  of  the  former,  as  is  shown  by  weights 
and  measurements  of  the  stocks  given  below.  A  calipering  of  these 
stocks  in  1S91  showed  no  appreciable  average  difference  in  diameter. 

DIAGRAM  1. — Showing  arrangement  of  treated  and  untreated  rows. 


EXPLANATION  OF  DIAGRAM  1. 

A  and  B,  treated  7  times  in  1891  and  G  times  iu  1892  with  Bordeaux;  C,  control  on 
row  opposite;  D  and  E,  treated  three  times  in  1S91  and  5  times  in  1892  with  Bor- 
deaux; F,  control  on  row  opposite.  This  portion  of  the  experiment  was  situated  on 
rows  VI,  VII,  and  VIII,  as  indicated  in  Table  2,  below,  and  in  the  plan  on  p.  257. 
The  unbudded  portion  alone  is  considered. 

TABLK  2. — Showing  ivcights  and  measurements  of  treated  and  untreated  French  pear  stocks 

in  November. 


• 

J  Average 

Kow. 

Section. 

Diagram 
designa- 
tion. 

Treatment. 

No.  of 
seed- 
lings. 

Average 

weight  as 
dug. 

fi>p. 

diameter 

at  collar, 
in  thirty- 

st-<  omlsof 

an  inch. 

Ounces. 

Ounces. 

VIII 

Bb  2 

A 

Bordeaux,  7  times  in  1891, 

6  times  in  1892  

57 

7.6 

6  4 

oo  o 

VII 

Cb  2 

B 

do 

(il 

8  8 

6  8 

°7  5 

vi 

DC 

0 

Untreated  in  1891  and  1892. 

57 

5.9 

4.0 

17.6 

VIII 

Bbl 

D 

Bordeaux,  3  times  in  1891, 

5  times  in  1892 

63 

9  1 

7  1 

23  1 

VII 

Cbl 

E 

do  .'-.. 

68 

7.8 

22  0 

VI 

Db 

F 

Untreated  in  1891  aud  1892. 

57 

5.9 

4.0 

17.6 

The  above  data  were  secured  in  the  following  manner:  The  first  week 
in  November  each  individual  stock  was  dug  carefully  and  the  dirt 
cleaned  from  the  roots.  It  was  then  calipered  and  weighed.  The  top 
was  then  cut  off  and  weighed  separately.  These  data  are,  perhaps, 
the  first  published  showing  the  superiority  of  treated  pear  seedlings  in 
other  respects  than  that  of  foliage.  As  regards  a  comparison  of  the 
two  copper  compounds,  it  will  be  sufficient  to  say  that  the  Bordeaux 
was  in  all  respects  superior  to  the  ammoniaca!  solution.  In  the  order 
of  their  eilieacy  the  four  methods  of  treatment  are  as  follows :  Bordeaux, 


245 

6  treatments ;  Bordeaux,  5  treatments;  ammouiacal  solution,  6  treat- 
ments; ammouiacal  solution,  5  treatments.  Five  treatments  with  the 
ammoniacal  solution  proved  almost  entirely  ineffectual.  Plate  xxin 
shows  the  average  of  stocks  treated  0  times  with  aiuuioniaeal  solution. 

JAPAN   PEAR    STOCKS. 

1891. — One  row  of  466  stocks  was  planted  in  a  manner  precisely  sim- 
ilar to  that  described  for  the  French  stocks.  The  dates  of  treatment 
were  as  above  given,  one  half  the  treated  portion  receiving  three  treat- 
ments and  the  other  seven,  one-half  being  treated  with  Bordeaux,  the 
other  with  ammoniacal  solution.  The  results  obtained  were  striking, 
as  illustrated  by  the  following  notes  on  the  re-leaved  stocks : 

TABLE  3. — Showing  number  of  Japan  stocks  forced  to  put  out  neiv  leaves. 


Number  and  treatment  of  stocks. 

Total  No. 
re  leaved. 

Per  cent 
re-leaved. 

87  stocks  treated  7  times  with  Bordeaux                          ..                 

1 

1.1 

88  stocks  treated  3  times  with  Kordeanx  .   

21 

2X8 

15 

17.2 

9U  (stocks  treated  3  times  with  ammoniacal  solution                             

9 

10.0 

114  stocks  untreated  

47 

41.2 

The  average  diameter  of  the  stocks  near  the  collar  was  not  percepti- 
bly greater  in  the  treated  than  in  the  untreated,  the  average  differ- 
ence amounting  to  less  than  one  thirty-second  of  an  inch.  The  un- 
treated Japan  stocks  suffered  more  from  the  disease  than  the  untreated 
French  stocks. 

1892. — The  same  row  of  stocks  as  that  employed  the  previous  season 
was  treated,  but  one-haff  or  more  of  the  stocks  were  budded  in  1891, 
as  described  subsequently  on  pp.  259,  261.  The  treatments  given  were 
as  described  on  pp.  262-263.  As  early  as  June  24  the  unbudded  stocks, 
which  had  not  been  treated,  showed  the  disease  plainly,  every  stock 
being  affected.  At  this  date  it  Avas  evident  that  the  Japan  stocks,  as 
introduced  from  the  south,  were  more  susceptible  to  leaf-blight  than  the 
imported  French  or  the  native-grown  American  stocks.  The  latter  were 
at  this  date  scarcely  affected  by  the  disease.  From  the  two  years' ex- 
periments upon  Japan  stocks  from  Franklin  Davis  &  Co.'s  nurseries  it 
seems  probable  that  these  when  imported  from  the  South  will  not  show 
any  greater  immunity  from  leaf-blight  than  the  French  or  American 
stocks.  A  more  extended  experiment,  however,  is  needed  to  settle  this 
point.  The  result  of  treatments  with  fungicides  was  as  striking  as  that 
gained  from  the  French  stocks.  The  foliage  on  the  budded  stocks  re- 
mained reasonably  free  from  the  disease  until  quite  late  in  September 
when  the  stocks  in  the  untreated  portions  began  to  drop  their  leaves 
badly;  those  treated  6  times  with  Bordeaux  held  their  leaves  almost 
intact.  The  Bordeaux  proved  in  general  more  efficacious  than  the  am- 
moniacal solution  in  the  treatment  of  both  budded  and  unbudded  stocks, 


246 


aud  6  treatments  were  more  effective  than  5.  But  one  noteworthy  ex- 
ception existed  in  the  first  section  treated  5  times  with  ammoniacal  solu- 
tion, which  is  possibly  explainable  by  superiority  of  soil. 

Below  are  given  in  Table  4  the  notes  on  foliage  and  caliper  made  Octo- 
ber 19,  1892: 

TABLE  4. — Showing  condition  of  Japan  stocks  as  regards  foliage  and  caliper. 


Section.* 

Treatment. 

Estimated  per  cent 
of  foliage  dropped. 

Average 
caliper 
of  un- 
budued  at 
collar  in  3*5 
of  inch. 

Budded 
stocks. 

Un- 
budded 
stocks. 

Aal 
Bal 
Cal 
Aa2 
Ba2 
Ca2 
Abl 
Bbl 
Cbl 
Ab2 
Bb2 
Cb2 
D-I 
D-II 
D-I  II 
D-IV 

Ammoniacal  solution  5  treatments 

0 
0 
80 
0 
0 
85 
0 
0 
40 
0 
0 
0 
15 

0 
80 
80 
50 
15 
60 
10 
25 
50 
5 
10 
0 

2G.6 
13.4 
15.0 
20.3 
24.7 
21.  G 
18.7 
19.7 
21.3 
21.5 
18.5 
23.1 

Do 

Do 

Ammonical  solution.  6  treatments 

Do 

Do  

Bordeaux  mixture  5  treatments  
Do  

Do 

Bordeaux  mixture  6  treatments 

Do  1 

Do  

Untreated  (budded)  

Do  

40 

95 

Do  

Untreated  (not  budded) 

98 

13.2 

*  Designations  in  this  column  refer  to  the  varieties  of  "buds,"  for  details  of  which,  see  p.  261. 

It  is  noticeable  from  the  above  table  that  Bordeaux  mixture  afforded 
the  greatest  immunity  5  also  that  the  untreated  unbudded  stocks  made 
much  less  growth  than  those  treated  with  Bordeaux.  A  reference  to 
the  plan  (p.  257)  will  show  the  situation  of  the  row  (No.  IX).  When  it 
is  remembered  that  of  all  of  the  French  stocks,  those  standing  in  row 
VIII  only  3J  feet  distant,  made  the  best  growth,  the  element  of  soil 
difference  is  hardly  to  be  considered  as  a  disturbing  factor. 

AMERICAN  PEAR   STOCKS. 

1891. — Four  rows  containing  1,673  stocks  were  subjected  to  a  course  of 
treatment  similar  in  every  respect  to  that  given  the  French  and  Japan 
stocks.  Owing  to  the  lateness  of  the  season  when  application  was  made 
to  the  growers  of  American  seedlings  only  second-grade  stocks  were  to 
be  obtained.  Because  of  this  unfortunate  but  unavoidable  circum- 
stance no  comparison  could  be  drawn  as  to  the  comparative  value  of 
American,  Japan,  and  imported  French  stocks.  The  results  of  the  treat- 
ments with  fungicides  while  not  as  striking  as  with  the  French  stocks,* 
are  valuable  as  adding  testimony  to  the  efficacy  of  the  Bordeaux.* 
Seven  treatments  with  this  mixture  proved  entirely  efficacious,  raising 
the  percentage  of  stocks  wholly  free  from  the  disease  from  two  tenths 
of  1  per  cent  to  39  per  cent.  On  October  9  a  count  was  made  of  the 


*See  Bull.  No.  3  Div.  Vcg.  Path.,  p.  59. 


247 


number  of  stocks  iu  each  section  which  pushed  out 
ol  the  severity  of  leaf-blight.     The  results  of  this 

TABLE  5. — Showing  number  of  American  stocks  forced  to 


cause 


Number  and  treatment  of  stocks. 


326  stocks  treated  7  times  with  Bordeaux 

288  stocks  treated  3  times  witli  Bordeaux 

313  stocks  treated  7  times  with  ammouiacal  solution 

325  stocks  treated  3  times  with  ammouiacal  solution 

421  stocks  untreated 


1802. — The  same  rows  of  stocks  were  employed  this  season  as  had 
been  treated  the  previous  season,  as  many  as  possible  of  them  having 
been  budded  as  described  subsequently  on  p.  261.  Those  not  budable 
were  left  standing  for  further  treatment  with  fungicides.  The  treat- 
ments were  as  described  on  pp.  262-263.  Owing  to  the  inferior  char- 
acter of  the  stocks  originally  planted  this  whole  block  would  be  consid- 
ered worthless,  as  not  one-half  the  stocks  were  budable  in  1891.  The 
effect  of  the  Bordeaux  mixture,  however,  was  plainly  observable  and  a 
rough  estimate  made  October  19  of  the  percentage  of  foliage  still  upon 
the  unb added  stocks  shows  the  Bordeaux  to  be  much  superior  to  the 
ammouiacal  solution,  and  6  treatments  superior  to  5. 

QUINCE  LEAF-BLIGHT  (Entomosporium  maculatum  Le"v.). 

Much  that  was  said  in  reference  to  pear  leaf-blight  applies  equally 
well  to  quince  leaf-blight,  which  is  caused  by  the  attacks  of  the  same 
fungus.  The  parasite,  so  far  as  the  author's  observation  goes,  never 
attacks  the  bark  on  the  young  shoots  but  is  confined  wholly  to  the 
foliage.  The  Angers  quince  seems  more  susceptible  than  the  Orange 
and  it  is  rare  to  observe  after  the  first  week  in  September  a  block  of 
quince  cuttings  from  which  at  least  50  per  cent  of  the  leaves  have 
not  fallen.  Unlike  the  disease  on  the  pear,  the  quince  leal-blight  often 
seriously  defoliates  bearing  trees  in  this  section  and  commonly  causes 
the  fruit-grower  much  loss  from  its  attacks  on  the  ripening  fruits,  iu 
which  form  it  is  called  "fruit  spot."* 

The  experiments  in  the  prevention  of  this  disease  were  confined  to 
one  row  of  Angers  quince  cuttings,  treated  partly  with  Bordeaux  mix- 
ture and  partly  with  ammouiacal  solution.! 

ANGERS  QUINCK  STOCKS. 

1891. — One  row  of  509  cuttings  was  planted  and  treated  with  fungi- 
cides in  the  manner  described  on  pp.  260-263.  The  season  being  an 
unusually  dry  one,  no  disease  of  any  consequence  appeared,  and  as 


"  Bull.  3  Div.  Veg.  Path.,  pp.  65-68,  PI.  vn,  vm. 

t  For  iorumlie  of  fungicides  ami  dates  of  treatment,  see  pp.  262-263. 


248 

stated  in  a  previous  publication  *  the  insignificant  quantity  of  leaf- 
blight  present  offered  no  opportunity  to  test  the  fungicides  in  a  satis- 
factory manner. 

1892. — The  same  row  of  cuttings  as  employed  in  1891  was  treated  this 
season,  but  one-half  or  more  of  each  section  had  been  budded  the  fall 
previous,  as  noted  below,  p.  2GO.  The  treatments  were  identical  with 
those  made  upon  the  pear  stock;  see  p.  262.  As  early  as  July  7  the 
leaves  on  the  untreated  section  left  without  budding  showed  the  dis 
ease  plainly,  while  the  foliage  of  those  sections  treated  with  Bordeaux 
and  arnmoniacal  solution  remained  free  from  the  disease.  By  August 
30  two-thirds  of  the  foliage  of  the  unbudded,  untreated  portion  had 
fallen  to  the  ground,  while  the  treated  sections  standing  in  the  same 
row,  as  shown  in  the  plan,  p.  257,  row  V,  remained  intact.  Plates  xxiv 
and  xxv  show  the  appearance  of  the  treated  and  untreated  sections. 

On  September  29  the  difference  manifested  by  these  stocks  was  not 
one  of  foliage  only.  The  twigs  of  the  treated,  upon  close  examina- 
tion, were  apparently  a  trifle  more  robust,  and  the  caliper  of  the  cut- 
tings at  the  base  showed  a  considerable  increase  not  to  be  attributed 
to  differences  in  soil.  Below  are  given  the  data  secured  from  a  careful 
calipering  of  the  unbudded  stocks  at  the  collar,  made  October  15.  The 
figures  given  are  in  thirty-seconds  of  an  inch  and  represent  the  aver- 
age diameter  of  stocks  in  each  section: 

TABLE  6. — Showing  average  caliper  of  treated  and  untreated  unlndded  quince  stocks. 


Section. 

Number  and  treatment  of  stocks. 

Average 
diameter. 

Aal 

25  3 

Bal 

16  stocks  treated  5  times  with  ammoiiiacal  solution      ... 

*>6  2 

Cal 

1C  stocks  treated  5  times  with  amuioniacal  solution  

2(i.  15 

Aa2 

25  0 

Ba2 

16  stocks  treated  6  times  with  aiuiuoniacal  solution  

27.0 

Ca2 

''I  0 

Abl 

15  stocks  treated  5  times  with  Bordeaux  mixture  

27.0 

Bbl 

Cbl 

16  stocks  treated  5  times  with  Bordeaux  mixture 

2f>  2 

Ab9 

2H  2 

Bb2 

17  stocks  treated  6  times  with  Bordeaux  mixture      

26  4 

*I)iv 

20  6 

*  Unfortunately  a  section.  Cb2,  was  not  staked  off  in  planning  the  experiment. 

The  inference  from  the  above  table  is  that  the  stocks  which  held 
their  leaves  through  the  season  made  a  greater  growth  in  diameter  than 
those  from  which  the  foliage  dropped  in  July  and  August.  Taking  the 
average  of  all  stocks  treated  with  ammoniacal  solution,  94  in  number,  we 
have  25.7  thirty-seconds  of  an  inch,  while  the  average  of  81  stocks 
treated  with  Bordeaux  was  26.5  thirty-seconds.  The  better  of  these  two 
averages  (2G.5)  when  compared  with  the  untreated  (20.6)  gives  an  in- 
crease in  diameter  of  5.9  thirty-seconds  or  nearly  three-sixteenths  of  an 
inch. 


*  Bull.  No.  3,  op.  cit.,  pp.  58-59. 


249 
CHERRY  LEAF-BLIGHT  (Cylindrosporium padi  Karsten). 

The  leaf-blight  of  cherries  caused  by  the  same  species  of  fungus  as 
that  producing  plum  leaf-blight,  is  very  widespread.  Scarcely  a  wild 
species  of  the  genus  Prunus  is  entirely  exempt  from  the  disease,  and  at 
all  stages  from  seedlings  in  the  seed  bed  to  old  bearing  trees,  cultivated 
cherries  are  subject  to  its  attacks.  The  greatest  variation  exists,  how- 
ever, as  regards  the  susceptibility  of  different  varieties,  some  being 
nearly  exempt  and  others,  as  the  English  Morello,  materially  damaged 
by  it.  Remarkable  cases  of  immunity  are  sometimes  observed.  Of 
seedlings  used  for  budding,  only  the  Mazzard  seems  in  any  serious  de- 
gree damaged  by  the  disease.  In  unfavorable  years  the  defoliation  is 
so  serious  as  to  render  the  first  year's  growth  of  stocks  almost  insig- 
nificant. Mazzard  seedlings  of  the  second  year  are  also  badly  attacked. 
The  greatest  damage  probably  occurs  where  Mazzard  stocks  are  budded 
with  susceptible  varieties,  in  which  case  the  cumulative  effects  of  the 
disease  appear.  It  should  be  noted  here,  however,  that  the  cherry 
leaves  attacked  by  the  parasite  remain  attached  to  the  stocks  long 
enough  to  take  on  the  yellow  autumn  tints  characteristic  of  foliage 
from  which  the  valuable  ingredients  of  potash  and  phosphoric  acid 
have  been  removed.*  It  is  probable,  although  no  experiments  have  to 
my  knowledge  been  made  to  establish  it,  that  the  premature  fall  of  the 
leaves  does  not  entail  so  great  a  loss  to  the  cherry  seedling  as  does 
the  fall  of  the  pear  foliage,  which  drops  while  still  green. 

The  experiments  in  the  prevention  of  this  disease,  extending  over  a 
period  of  two  seasons,  were  made  upon  the  two  well-known  kinds  of 
stocks,  Mahaleb  and  Mazzard.  In  1891  only  the  stocks  not  yet  budded 
were  treated,  while  in  1892  the  stocks  budded  in  the  fall  of  1891  were 
sprayed,  suitable  control  being  left. 

For  record  of  budding  see  pp.  258,  2GO.  Bordeaux  mixture  and  am- 
moniacal  solution  of  standard  strength  were  employed  in  1891;  ammo- 
niacal  solution  of  standard  strength  and  Bordeaux  of  one-third  strength 
in  1892.1 

JtfAHALEB   CHERRY   STOCKS. 

1891. — One  row  of  449  stocks  was  planted  and  treated  with  fungicides 
at  the  dates  described  for  all  the  stocks  on  p.  263.  One-half,  excepting 
controls,  received  6  and  the  other  3  sprayings.  One-half  were  treated 
with  ammoniacal  solution,  the  other  with  Bordeaux.  As  mentioned  in 
Bulletin  No.  3,J  where  an  account  of  this  experiment  has  already  been 

'According  to  the  prevailing  views  of  tlie  physiological  botanists,  Pfeifer,  Sachs, 
Detiner,  Wiesner,  and  others,  the  valuable  mineral  constituents  of  leaves  aje  with- 
drawn from  them  at  the  same  time  as  they  become  yellow  and  before  they  fall  to  the 
ground;  but  the  recent  paper  of  Wehmer,  Die  dem  Laulfall  voraufyehende  vermeint- 
Uche  flatten tleerung.  <#«-.  d.  denhch.  lot.  Gesellsch.  10  Jahrg.,  Heft.  3,  pp.  152-163, 
indicates  that  the  grounds  for  this  belief  may  not  have  been  sufficiently  proven,  and 
the  whole  subject  needs  further  investigation. 

t  See  p.  262  for  formulae  of  all  fungicides  used. 

tOp.  cit.,-p,  58. 


250 


given,  the  leaf-blight  was  not  present  in  any  considerable  amount  dur- 
ing the  season  and  the  efficacy  of  the  two  fungicides  was  not  given  a 
test  of  any  severity.  The  treated  portions,  however,  remained  freer 
from  disease  than  the  untreated. 

1892. — The  same  row  which  had  been  budded  in  the  fall  of  1891  as 
described  subsequently,  was  treated  this  season  in  a  manner  precisely 
similar  to  that  described  for  the  pear  stocks  on  page  263.  Care  was  taken 
that  the  undersides  of  the  leaves  were  wet  by  the  spray  and  to  ac- 
complish this  the  Vermorel  nozzle  was  directed  upwards.  On  June  24 
the  first  signs  of  leaf  blight  were  noticed  upon  the  budded,  untreated, 
stocks,  the  unbudded  stocks  remaining  almost  entirely  free  throughout 
the  season.  By  July  10  the  leaves  of  the  untreated  began  to  fall  and 
continued  dropping  until  many  of  the  stocks  were  left  nearly  leafless. 
On  October  4  a  careful  count  was  made  of  the  number  of  leaves 
which  had  fallen  from  each  individual  stock  in  the  row.  This  was  ac- 
complished, in  a  comparative  way,  by  counting  the  leaf  scars  on  each 
stock.  Below  is  given  for  convenience  a  condensed  statement  of  the 
condition  of  the  stocks  with  regard  to  height,  diameter  3  inches  above 
the  union,  and  freedom  from  leaf-blight.  All  numbers  represent  aver- 
ages. Height  above  ground  (measured  September  28)  is  represented 
in  feet  and  inches,  while  the  figures  for  diameter  (measured  October  15) 
are  in  thirty  seconds  of  an  inch.  Only  budded  stocks  are  here  taken 
into  account. 

TABLE  7. — Showing  condition  of  budded  Malialeb  stocks,  treated  and  untreated,  as  regards 

foliage  and  measurements. 


Section. 

Numbers,  kinds,  and  treatment  of  stocks. 

Average 
number 
of  leaves 
fallen 
October  4. 

Average 
height  above 
ground. 

Average 
calipt-r 
3  indies 
above 
union. 

Aal 
Aa2 
Abl 
Ab2 

D-II1 
Bal 

Ba2 
Ebl 
lib  2 

D-I1 
Cal 

Ca  2 
Cbl 
Cb2 
D-I 

16  budded  Windsor  stocks.    Ammoniacal,  5 

8.0 
7.8 
13.1 

7.4 
54.8 

6.4 
6.4 
7.3 

4.8 
21.3 

8.5 
10  3 

Feet. 
5 

5 
6 

6 
5 

4 
4 
5 

5 
4 

3 
3 
3 

3 
| 

Inches. 
8 

10 
0 

0 
() 

9 
9 
4 

1 
1 

7 

r> 
s 

9 

I 

23 
23 
24 

25 
16 

22 
21 
21 

23 
16 

21 

21 
~£ 
21 

19 
17 

18  budded  Windsor   stocks.    Ammoniacal,  6 

13  budded  Windsor  stocks.  Bordeaux,  5  treat- 
ments   

17  budded  Windsor  stocks.  Bordeaux,  6  treat- 
ments           .     .   . 

7  budded  Windsor  stocks.     Untreated  

18  budded  Yellow  Spanish   stocks.     Ammo- 
niacal  5  treatments 

17  budded  Yellow  Spanish  stocks.    Amniom- 

18  budded  Yellow  Spanish  stocks.   Bordeaux, 

18  budded  Yellow  Spanish  stocks,  Bordeaux, 
6  treatments  

8  budded  Yellow  Spanish  stocks.    Untreated.  . 
16  budded  Moutmorency  stocks.  Ammoniacal, 

18  budded  Montmoreucy  stocks.  Ammoniacal, 

22  budded  Montmorency  stocks.     Bordeaux, 

4.0 

fi.  1 
65.7 

16  budded  Montmorency  stocks.    Bordeaux, 

4  budded  Montmorency  stocks.    Untreated  .  .  . 

251 

The  conclusion  which  can  be  drawn  from  the  table  seems  to  be  that 
the  treated  sections  held  their  leaves  better,  made  as  good  a  growth  in 
height,  and  without  exception  a  greater  growth  in  diameter,  or  "eali- 
pcr,"  than  the  untreated  sections.  That  this  increased  growth  was  due 
ent  irely  to  the  fungicide  it  will  not  be  possible  to  maintain,  for  this  differ- 
ence may  possibly  have  been  brought  about  in  part  or  wholly  by  varia- 
tions in  the  soil.  That  none  of  the  mixtures  injured  the  "buds"  it  is 
believed  is  clearly  shown. 

The  answer  to  question  3,  as  to  the  effect  of  fungicides  on  the  growth 
of  budded  stocks  is  here,  for  the  Bordeaux  mixture  at  least,  satisfac- 
torily found,  for  both  Windsor  and  Yellow  Spanish  stocks  did  better 
under  treatment  with  Bordeaux  than  without  treatment.  There  still 
remains  a  doubt  as  to  the  beneficial  effect  of  ammoniacal  solution. 
In  all  cases  where  used  it  was  apparently  slightly  injurious  to  the 
foliage.  The  leaves  assumed  a  yellowish  unhealthy  appearance.  Plates 
xxvi  and  xxvn  show  the  comparison  between  treated  and  untreated 
"buds." 

MAZZARD    CHERRY    STOCKS. 

1891. — One  row  of  468  stocks  was  experimented  with,  receiving  as 
nearly  as  possible  a  course  of  treatment  identical  with  that  given  the 
Mahaleb  stocks.  During  the  season,  as  in  the  case  of  the  Mahalebs, 
only  an  insignificant  amount  of  leaf-blight  was  present,  affording  no 
opportunity  to  test  the  fungicides.  The  powdery  mildew  (Podosphccra 
oxyacantlice  (DC.)  Winter  f)  made  its  appearance  in  small  amount  on 
the  stocks  in  August  and  offered  an  opportunity  to  observe  the  bene- 
ficial effects  of  Bordeaux  mixture  in  the  treatment  of  this  disease. 
Seven  treatments  with  Bordeaux  materially  decreased  the  amount  of 
the  disease  and  proved  superior  to  seven  treatments  with  ammoniacal 
solution.*  Three  early  treatments  with  either  fungicide  had  no  pre- 
ventive effect. 

1892. — The  same  row  as  that  treated  in  1891  was  used  this  season, 
but  budded  with  three  different  varieties  identical  with  those  budded 
on  the  Mahaleb  stocks  as  shown  in  the  table  on  p.  200.  The  treat- 
ments were  similar  in  all  respects  to  those  given  the  Mahaleb  stocks. 
The  condition  of  the  stocks  at  the  close  of  the  season  is  shown  by  the 
following  table: 

~  *Soe  Bull.  No.  3  Div.  Veg.  Path.,  1802,  p.  58. 


252 


TABLE  8. — Showing  condition  of  budded  Mazzard  stocks  treated  and  untreated  as  regards 

foliage  and  measurements. 


Section. 

Number,  kinds,  and  treatment  of  stocks. 

Average 
number 
of  leaves 
fallen 
Oct.  10. 

Average  height 
above  ground. 

Average 
caliper  3 
inches 
above 
union. 

Aal 
Aa2 
Abl 
Ab2 

D-I* 
Bal 

Ba2 
Bbl 
Bb2 

D-II 

Gal 

Ca2 
Cbl 
Cb2 
D-III 

25  budded  Windsor    stocks;   ammoniacal,     5 
treatments  

5.0 
5.3 
6.4 

5.3 
13.7 

4.2 
4.6 
2.9 

2.5 

8.7 

6.3 
6.8 
5.9 

5.0 
24.2 

Feet. 
4 

5 
5 

5 
4 

4 
4 
5 

4 
3 

3 

3 
3 

3 
2 

I'lchcu. 
10 

6 
9 

10 
9 

5 
10 
6 

5 
2 

7 
3 
1 

1 
8 

10 
20 
20 

20 
20 

19 
21 
18 

18 
15 

18 
17 
17 

17 
14 

30  budded  Windsor    stocks;    ammoniacal,  6 
treatments  

27    budded    Windsor    stocks;    Bordeaux,    5 
treatment's  

27    budded    Windsor    stocks;    Bordeaux,    6 
treatments.        

11  budded  Windsor  stocks  ;  untreated  

27  budded  Yellow  Spanish  stocks  ;  ammonia- 

28  budded  Yellow  Spanish  stocks;  ammonia- 
cal, 6  treatments  

31  budded  Yellow  Spanish  stocks  ;  Bordeaux, 
5  treatments.  

31  budded  Yellow  Spanish  stocks  ;  Bordeaux, 

14  budded  Yellow  Spanish  stocks  ;  untreated. 
26  budded  Montmorency  stocks  ;  ammoniacal, 

18  budded  Montmorency  stocks  ;  ammoniacal, 

26  budded  Montmorency  stocks;  Bordeaux,  5 

26  budded  Montmorency  stocks;  Bordeaux,  6 
treatments  

7  budded  Montmorency  stocks;  untreated  

*  By  an  accident  this  section  received  one  late  spraying  with  Bordeaux  and  hence  it  is  rendered  un- 
fit for  comparison . 

The  disease  did  comparatively  little  damage  upon  these  stocks,  but 
as  shown  by  the  table,  the  treated  sections  were  superior  to  the  un- 
treated, and  the  Bordeaux  slightly  superior  to  the  ammoniacal  solution 
when  6  treatments  are  compared.*  The  difference  between  5  and  6 
treatments  was  not  very  marked. 

A  comparison  of  the  two  tables  brings  out  the  fact  which  is  note- 
worthy in  this  connection,  that  the  ubuds"t  on  Mahaleb  stocks  aver- 
aged greater  in  diameter  throughout  than  those  on  the  Ma/zard.  This 
difference  is  constant  when  stocks  receiving  the  same  treatment  are 
compared  in  each  row,  with  the  exception  of  the  untreated  section  of 
Windsors  when  compared  with  that  treated  once  by  mistake.  This 
constant  difference  in  diameter,  at  3  inches  above  the  base  ("  caliper"), 
is  of  such  importance  as  to  merit  further  observations.  The  author  re- 
grets that  the  control  rows  were  left  so  small,  and  feels  warranted  in 
drawing  only  the  general  conclusion,  which  was  strikingly  demonstrated 
that  the  fungicides  were  effective  to  a  remarkable  degree  in  preventing 
the  disease  and  that  treated  stocks  made  the  best  growth. 

*The  superiority  of  Bordeaux  is  not  fully  sho\vn  by  the  figures,  as  in  every  case 
the  effect  of  the  ammoniacal  solution  was  evidently  injurious  to  the  health  of  the  foli- 
age. 

tThe  term  "bud"  is  here  used,  as  among  nurserymen,  to  indicate  a  budded  stock 
after  the  top  has  been  cut  off  and  the  iuserted  bud  itself  allowed  to  grow. 


253 
PLUM  LEAF-BLIGHT  (Cylindrosjjorium padi  Karsten.) 

The  plum  leaf-blight  in  western  New  York,  aside  from  giving  much 
trouble  to  nurserymen,  does  very  great  damage  to  many  varieties  of 
bearing  trees,  defoliating  them  in  August  and  September.  This  disease 
is  considered -by  the  plum-growers  in  the  vicinity  of  Geneva  as  their 
most  persistent  enemy.  A  large  orchard  belonging  to  E.  Smith  &  Sous, 
2  miles  northwest  of  the  city,  was,  they  informed  me,  winter-killed 
about  thirty  years  ago  because  of  defoliation  the  summer  previous.  It 
is  a  common  opinion  among  orchardists  that  leaf-blight,  through  its 
retarding  effect  upon  the  maturation  of  the  wood,  renders  the  trees 
incapable  of  withstanding  the  changes  in  temperature  of  a  trying  win- 
ter. Whatever  the  explanation  of  this  fact  may  be,  it  seems  self-evi- 
dent that  a  tree  which  drops  its  leaves  before  the  normal  season  suf- 
fers very  material  loss. 

Of  nursery  stocks,  the  native-grown  seedlings  suffer  the  most  from 
this  disease,  often  losing  all  their  leaves  by  the  middle  of  August.  My- 
robolan  and  Marianna  stocks  are  not  to  any  extent  subject  the  first 
season.  In  entire  contradistinction  to  the  immunity  exhibited  by 
pear  "  buds  "  which  resist  to  a  remarkable  degree  pear  leaf-blight,  the 
budded  plum  stocks  are  particularly  susceptible  to  pluni  leaf-blight. 
Apparently  the  same  conditions  of  rapid  growth  which  afford  immunity 
in  the  one  case  tend  to  susceptibility  in  the  other.  The  two  instances 
offer  a  fertile  field  for  inquiry. 

The  experiments  on  this  disease  were  made  with  Bordeaux  mixture 
and  ammoniacal  solution  upon  two  rows  of  stocks,  one  of  Mariajina, 
containing  504  stocks,  and  the  other  of  Myrobolan,  containing  474 
stocks.  As  described  previously  *  the  results  of  the  first  season's  ex- 
periment were  entirely  negative,  as  the  disease  failed  to  appear. 

On  October  9  the  three  varieties,  Early  Prolific  (Early  Elvers),  Pur- 
ple Egg  (Hudson  Kiver  Purple  Egg),  and  Italian  Prune  (Fellenburg), 
were  budded  upon  both  rows  of  stocks  as  set  forth  subsequently,  p.  258. 
Numerous  stocks  were  left  unbudded  to  test  the  effect  of  the  fungicides 
and  the  end  of  each  row  was  left  untreated. 

The  rows  were  treated  in  1802  with  Bordeaux  and  ammoniacal  solu- 
tion, the  formula  of  which  are  described  on  p.  262.  One-half  the 
treated  stocks  received  5  sprayings  and  the  other  6,  at  the  dates  given 
on  p.  243.  In  all  respects  the  two  rows  were  treated  alike. 

MYROBOLAN  STOCKS. 

1892. — The  disease  made  its  first  appearance  in  June  upon  the  un- 
budded stocks  which  were  carried  over  from  1891,  and  strangely 
enough  only  upon  the  treated  portions.  This  dropping  of  the  treated 
Myrobolan  foliage  was  confined  to  the  leaves  situated  on  the  larger 

*  Bull.  No.  3  Div.  Veg.  Path.,  p.  58. 
16486— No.  3 5 


254 


limbs  in  the  interior  portion  of  the  bushy  growtn.  Although  only  a 
small  per  cent  of  the  foliage  was  thus  affected,  the  difference  between 
treated  and  untreated  was  quite  evident.  After  the  lapse  of  three 
or  four  weeks  this  falling  of  the  leaves  ceased.  The  unbudded  stocks 
which  were  not  treated  remained  remarkably  free  from  the  disease, 
but  in  this  respect  were  excelled  by  the  Marianna  unbudded,  untreated 
stocks.  The  budded  stocks  were  not  so  soon  affected  as  the  unbudded, 
but  the  Early  Prolific  "buds  "in  the  untreated  section  began  dropping 
their  foliage  in  July  and  throughout  the  season  were  manifestly  worse 
affected.  The  following  table  shows  the  data  collected  in  September 
and  October)  after  all  growth  had  practically  ceased : 

TABLE  9. — Showing  condition  of  budded  Myrobolan  stocks  treated  and  untreated,  as  re- 
gards foliage  and  measurements. 


Section. 

Number,  kinds,  and  treatment  of  stocks. 

Average 
number 

ofleaves 
fallen  Oc- 
tober 10. 

Average 
height  above 
ground  Sep- 
tember 28. 

Average 
C}ili]-er3in- 
I'hes  above 
union  Oc- 
tober 15. 

Aal 
Aa2 
Abl 
Ab2 

D-I 
Bal 

Ba2 
Bbl 
Bb2 

D-II 
Cal 

Ca2 
Cbl 
Cb2 
D-III 

11  budded  Early  Prolific  stocks,  ammoniacal, 
5  treatments  

69.8 
115.8 
66.0 
57  5 

Feet. 
3 
3 
4 

3 
3 

4 
4 
3 

4 
4 

3 
3 
3 

4 
3 

Inches. 
6 
6 
0 

8 
9 

1 

2 
8 

3 

7 

10 
7 
6 

0 
9 

14.8 
14.3 
15.4 

16.9 
14.3 

16.  2 
15.1 
15.4 

15.  6 
16.4 

14.3 
15.3 
15.5 

16.4 
15.0 

16  budded  Early  Prolific  stocks,  ammoniacal, 
6  treatments  

18  budded  Early  Prolific  stocks,  Bordeaux,  5 
treatments  .     ... 

13  budded  Early  Prolific  stocks,  Bordeaux,  6 
treatments 

8  budded  Early  Prolific  stocks,  untreated  
13  budded  Purple  Egg  stocks,  amraoniacal,  5 
treatments  

812.5 

36.3 
32.8 
6.1 

9.7 
123.3 

15.8 
8.2 

7.8 

6.3 

52.8 

20  budded  Purple  Egg  stocks,  ammoniacal,  6 
treatments  

16  budded  Purple  Egg  stocks,   Bordeaux,  5 
treatments       

16  budded  Purple  Egg  stocks,   Bordeaux,  6 
treatments 

10  budded  Purple  Egg  stocks,  untreated  
12  budded  Italian  Prune  stocks,  ammoniacal, 
5  treatments  

16  budded  Italian  Prune  stocks,  ammoniacal, 

16  budded  Italian  Prune  stocks,  Bordeaux,  5 
treatments       .          -         

15  budded  Italian  Prune  stocks,  Bordeaux,  6 

11  budded  Italian  Prune  stocks,  untreated  

From  this  table  the  only  conclusion  admissible  is  in  regard  to  the 
amount  of  leaf-blight.  It  is  evident  that  the  treated  portions  lost  only 
a  small  number  of  leaves  in  comparison  with  the  untreated,  and  in  so 
far  the  fungicides  proved  effective. 

MARIANNA   STOCKS. 

1892. — The  treatment  of  these  stocks  was  in  all  respects  identical 
with  that  of  the  Myrobolan  stocks  and  the  results  were  in  general  sim- 
ilar. The  treated  unbudded  stocks  lost  a  number  of  their  leaves  from 
an  early  attack  of  the  fungus  in  June  and  July,  but  the  untreated  un- 
budded portion  of  the  row  remained  remarkably  free  from  the  disease 
throughout  the  season,  more  so  in  this  regard  than  the  Myrobolan.  The 


255 


budded  stocks  showed  little  superiority  in  regard  to  leaf-blight  over 
the  budded  Myrobolaii  and  evidently  no  considerable  degree  of  immu- 
nity was  afforded  by  the  stock  to  the  scion.  But  a  comparison  of  the 
two  tables  brings  out  the  fact  that  the  Purple  Egg  "buds"  made  mark- 
edly the  best  growth  upon  Mariaima  stocks.  These  "buds"  averaged 
more  than  one-eighth  of  an  inch  greater  in  diameter  and  were  on  an 
average  10  inches  higher.  The  other  less  rapidly  growing  stocks  did 
not  show  such  a  marked  difference,  and  too  much  reliance  ought  not 
to  be  placed  on  data  gathered  from  so  small  a  number  of  stocks.  Cer- 
tain it  is,  however,  that  the  Marianna  proved  superior  in  this  single 
experiment. 

TABLE  10. — Showing  condition  of  budded  Marianna  stocks,  treated  and  untreated,  as  re- 
gards foliage  and  measurements. 


Section. 

Number,  kinds,  and  treatment  of  stocks. 

Average 
number 
of  leaves 
fallen  Oc- 
tober 11. 

Average  heigh  t 
above  ground 
September  28. 

Average 
caliber  3 
inches  above 
union,  Oc- 
tober 15. 

Aal 
Aa2 

Abl 
Ab2 

D-I 
Bal 

Ba2 
Bbl 
Bb2 

D-II 
D-III* 
Cal 

Ca2 
Cbl 
Cb2 

9  budded  Early  Prolific  stocks,  ammoniacal,  5 

98.8 
63.3 
99.6 

71.6 
311.2 

39.1 
45.1 
42.7 

26.9 
143.2 
177.2 

16.8 
17.5 
11 
12.2 

Feet. 

3 
3 
4 

3 
3 

5 
4 
5 

5 
5 
4 

3 
4 
4 
4 

Inches. 
3 
6 
4 

2 

7 

5 

7 
0 

1 
0 

11 

6 

0 

7 
2 

Inches. 
15.5 
16.3 
20.2 

18.5 
15.9 

21.2 
20.6 
21.  3 

20.2 
20.5 
19.2 

17.2 
14.5 
20 
19 

li  budded  Early  Prolific  stocks,  ammoniacal, 
6  treatments  

14  budded  Early  Prolific  stocks,  Bordeaux,  5 
treatments         ..     -  -  . 

5  budded  Early  Prolific  stocks,  Bordeaux,  6 
treatments                     .          

10  budded  Early  Prolific  stocks,  untreated  
17  budded  Purple  Egg  stocks,  ammoniacal,  5 

23  budded  Purple  Egg  stocks,  ammoniacal,  6 

17  budded  Purple  Egg  stocks,   Bordeaux,  5 

21  budded  Purple  Egg  stocks,    Bordeaux,  6 
treatments  

14  budded  Purple  Egg  stocks,  untreated  
12  budded  P  urple  Egg  stocks,  untreated  
19  budded  Italian  Prune  stocks,  ammoniacal, 
5  treatments  

24  budded  Italian  Prune  stocks,  ammoniacal, 
6  treatments  

20  budded  Italian  Prune  stocks,  Bordeaux,  5 

19  budded  Italian  Prune  stocks,  Bordeaux,  6 
treatments 

*  By  another  mistake  in  budding,  those  stocks  which  should  have  received  Italian  Prune  buds  were 
budded  with  Purple  Egg  buds. 

As  regards  the  effects  of  the  treatments,  the  only  fairly  deducible 
conclusion  is  that  the  Bordeaux  mixture  and  ainmoniacnl  solution  pre- 
vented the  disease  to  a  notable  degree,  sufficient,  it  is  believed,  to 
warrant  further  extended  trial  in  nursery  practice.  Although  not 
evident  from  the  table,  the  ammouiacal  solution  is  in  reality  inferior  to 
Bordeaux,  as  it  injures  the  foliage  of  the  treated  "buds."  On  this 
account  it  can  not  be  recommended  for  the  treatment  of  plum  stocks. 
Plates  xxvin  and  xxix  show  the  treated  and  untreated  "buds"  as 
they  appeared  in  the  experiments. 


256 
APPLE  POWDERY  MILDEW  (Podospiuvra  oxyacantlicB  (DC)  Winter?), 

Seedling  apples  sometimes  suffer  quite  severely  from  this  disease, 
which  attacks  their  young  shoot  tips,  often  stunting  the  growth  of  the 
seedlings  and  preventing  them  from  attaining  a  suitable  size  the  first 
season.  Compared  with  the  injury  caused  by  the  apple  thrips,  how- 
ever, that  brought  about  by  mildew  is  surely  insignificant  and,  in  New 
York  State  at  least,  hardly  warrants  any  expensive  measures  for  its 
prevention.  The  disease  usually  appears  late  in  September,  when  the 
principal  growth  has  been  made,  and  seldom,  if  ever,  spreads  to  vig- 
orously growing  budded  stocks,  even  when  these  are  in  close  prox- 
imity to  diseased  seedliugs.  The  malady  was  not  observed  on  bearing 
trees  in  the  neighborhood  of  Geneva. 

The  experiments* for  the  prevention  of  this  disease  comprised  in  1891 
about  1,000  American  stocks  and  the  same  number  of  French  stocks, 
besides  500  seedlings.  As  stated  in  a  previous  publication,*  the  results 
of  the  first  season's  treatment  of  the  stocks  was  entirely  negative  and 
the  treatments  of  seedlings  which  were  made  on  May  21,  June  3,  24, 
July  9,  24,  and  August  8,  as  well  as  the  early  treatments  made  on  the 
first  three  dates  mentioned,  failed  entirely  to  prevent  the  appearance 
of  mildew  the  first  week  in  September.  Bordeaux  mixture  and  am- 
inoniacal  solution  alone  were  used,  the  formulae  being  those  described 
on  p.  262.  This  failure  of  the  fungicides  is  considered  by  the  author 
merely  as  additional  testimony  to  the  fact  observed  that  the  mixtures 
were  largely  washed  off  before  the  disease  appeared.  On  August  7  the 
French  and  American  stocks  were  budded  with  Twenty  Ounce,  Fameuse 
and  Early  Strawberry  buds,  as  described  in  detail  on  p.  259,  and  in  the 
season  of  1892  the  budded,  and  such  of  the  stocks  as  were  left  unbudded 
were  treated  with  Bordeaux  mixture  and  ammoniacal  solution  at  dates 
the  same  as  for  all  other  stocks,  viz,  May  27  5  June  16,  23;  July  7,  21; 
and  August  5.  One-half  the  treated  stocks  were  sprayed  5  times  on 
the  first  five  dates  mentioned,  the  other  half  were  sprayed  6  times. 

No  powdery  mildew  appeared  during  the  course  of  the  season,  and  in 
October  the  results  of  the  treatments  were  entirely  negative.  The  ap- 
ple thrips,  however,  attacked  the  budded  and  unbudded  stocks  and 
injured  them  severely.  The  mixtures  had,  as  might  be  expected,  no 
effect  upon  these  insects. 

DETAILS   OF   THE  EXPERIMENTS. 

The  following  pages  comprise  the  details  of  the  experiments,  which 
are  removed  from  the  general  account  in  order  to  render  the  latter  more 
comprehensible.  They  will  prove  of  interest  only  to  specialists  on  the 
subject. 

"Bull.  No.  3,  loc.  cit.,  p.  60. 


257 

DIAGRAM  2. — Plan  of  nursery  experiment  at  Genera,  N.  T. 

A  B  C  PI.     Pit.    DIH.   DIV. 


A B  C PI.     Pit.    Dill.   DIV. 


A  B  C  PI.     PH.    pill.   DIV. 

A B  C PI.     Oil.    Dill.   DIV. 

IV.         •'•••  •  " '"  — 

V  A  B  ^^  C  PI.     PH.    pill.   DIV. 

D\. DH. DIM.  DIV.  


vn. 


vni.   -2. 


IX          A  B  C       |         [  PI.   pll.  plH.plV. 

Dl.  DH.  Dill.  DIV. 


X. 


XL        £, 


XIV       °                                              ^                                                   Dl.    PH.  D IH.  DIV. 
XV.        A  B 


XVII. 


Dl.    Dll.   Dill.  DIV. 


XX.  A  B  C  Dl.    DM.  Dill.  DIV. 
y  VTTT            |                            XIX.               PEAR  SEED^ WORTHLESS. 

XXI.  t 

xxii.        • 


— — —  Treated  3  to  5  times  with  ammoniacal  solution,  fa  1). 
•"••••"•  Treated  6  to  7  times  with  ammoniacal  solution >  (a  2J, 
i  Treated  4  times  with  mixture  No.  13. 

Untreated. 

•    •  Treated  3  to  5  times  with  Bordeaux,  (1)1). 
i  Treated,  6  to  7  times  with  Bordeaux,  (  b  2). 

The  actual  proportions  of  the  experimental  Held  do  not  admit  of  any  but  a  dia- 
grammatic representation.  The  location  of  the  field  is  designated  in  the  records  of 
the  station  as  "main  farm  plat  B."  The  rows  ran  east  and  west,  the  west  end  of 
each  row  being  indicated  by  a  Roman  numeral.  These  numerals  are  for  conven- 
ience of  reference  (see  account  following).  The  capital  letters  heading  the  sections 
of  each  row  refer  to  the  budding.  For  example:  Row  I,  Section  A,  was  budded  with 
Windsor;  Row  I,  Section  B,  with  Yellow  Spanish,  precisely  as  set  forth  below. 
The  treatments  with  fungicides  which  each  section  and  subsection  received  arc 
indica  ted  by  the  key  below  Diagram  2. 


258 

The  sections  of  the  various  rows  were  budded  as  below  described. 
Row  I.  Mahaleb  cherry  stocks  budded  August  5,  1891t 
Section      A  with  Windsor. 

B  with  Yellow  Spanish. 
C  with  Montniorency. 
Di  with  Montmorency. 
Dn  with  Yellow  Spanish. 
Dm  with  Windsor. 
Div  unb added. 

Row  II.  Mazzard  cherry  stocks  budded  August  5>  1891. 
Section      A  with  Windsor. 

B  with  Yellow  ^punish. 
C  with  Montmorency. 
Di  with  Windsor. 
Dn  with  Yellow  Spanish. 
Dm  with  Montniorency. 
Div  unbudded. 

Row  III.  Myrobolan  plum  stocks  budded  September  10, 1891. 
Section      A  with  Early  Prolific. 
B  with  Purple  Egg. 
C  with  Italian  Prune. 
Di  with  Early  Prolific. 
Dn  with  Purple  Egg. 
Dm  with  Italian  Prune. 
Div  unbudded. 

Row  IV.  Marianna  plum  stocks  budded  September  10,  1891. 
Section      A  with  Early  Prolific. 
B  with  Purple  Egg. 
C  with  Italian  Prune. 
Di  with  Early  Prolific. 
Dn  with  Purple  Egg.* 
Dm  with  Purple  Egg.t 
Div  unbudded. 

Row  V.  Angers  quince  stocks  budded  August  6,  1891. 
Section      A  with  Duchess. 
B  with  Anjou. 
C  with  Flemish  Beauty. 
Di  with  Duchess. 
Dn  with  Anjou. 
Dm  with  Anjou. 
Div  unbudded. 

Row  VI.  French  pear  stocks  budded  August  7, 1891. 
Section    Di  with  Duchess. 
Dn  with  Anjou. 
Dm  with  Flemish  Beauty. 
Div  unbudded. 
Row  VII.  French  pear  stocks  budded  August  7,  1891. 

Section  C  with  Flemish  Beauty. 

Row  VIII.  French  pear  stocks  budded  August  7,  1891. 
Section  B  with  Anjou. 

*  A  variety  of  recent  introduction  originated  on  the  Hudson  River, 
t  The  budder's  blunder  in  inserting  these  in  place  of  Italian  Prune, 


259 

Row  IX.  Japan  pear  stocks  budded  August  5,  1891. 
Section        A  with  Duchess. 
B  with  Anjou. 
C  with  Flemish  Beauty. 
Di  with  Duchess. 
Dn  with  Anjou. 
Dm  with  Flemish  Beauty. 
Div  unbudded. 

Row  X.  American  pear  stocks  budded  August  7,  1891. 
Section      Di  with  Duchess. 
Dn  with  Anjou. 
Dm  with  Flemish  Beauty. 
Div  unbudded. 
Row  XI.  American  pear  stocks  budded  August  7,  1891. 

Section  C  with  Flemish  Beauty. 
Row  XII.  American  pear  stocks  budded  August  7,  1891. 

Section  B  with  Anjou. 
Row  XIII.  American  pear  stocks  budded  August  1,  1891. 

Section  A  with  Duchess. 

Row  XIV.  American  apple  stocks  budded  August  7,  1891. 
Section        C  with  Twenty  Ounce. 
Di  with  Fanieuse.         ., 
Dn  with  Early  Strawberry. 
Dm  with  Twenty  Ounce. 
Div  unbudded. 

Row  XV.  American  apple  stocks  budded  August  7,  1891. 
Section  A  with  Fameuse. 

B  with  Early  Strawberry. 

Row  XVI.  French  apple  stocks  budded  August  7,1891. 
Section        C  with  Twenty  Ounce. 
Di  with  Fameuse. 
Dn  with  Early  Strawberry. 
Dm  with  Twenty  Ounce. 
Div  unbudded. 

Row  XVII.  French  apple  stocks  budded  August  7, 1891. 
Section  A  with  Fameuse. 

B  with  Early  Strawberry. 
Row  XVIII.  French  apple  seeds. 

Row  XIX.  French  pear  seeds  which  did  not  germinate. 
Row  XX.  Peach  seedlings  which  remained  healthy. 
Row  XXI.  French  pear  stocks  budded  August  7, 1891. 

Section  A  with  Duchess. 

Row  XXII.  Plum  seedlings  of  Prnnns  domestica.* 
Row  XXIII.  Horse  chestnut  seedlings.  * 

*  The  results  of  treatments  of  plum  and  horse  chestnut  seedlings  are  reserved  for 
future  publication. 


260 


TABLE  11. — Shoiving  tlie  number  of  budded  stoclcs  in  each  treated  and  untreated  section. 

[The  small  letter  a  indicates  that  the  stocks  were  treated  with  amnionical  solution,  the  letter  6  1'ihat 
they  were  sprayed  with  Bordeaux.  The  Arabic  numeral  1  indicates  that  the  stocks  were  treattvl  5 
times,  the  number  2  that  they  were  treated  6  times.  The  sections  marked  I-TV  were  not  treated.  ] 


Row. 

Kind  of  stock. 

Section. 

Variety  of  bud. 

Number 
budded, 

Number 
left  un~ 
budded. 

I 
II 
in 

IV 

v 

Mahalcb 

Aal 
Aa2 
Abl 
Ab2 
Bal 
Ba2 
Bbl 
Bb2 
Cal 
Ca2 
Cbl 
Cb2 
Dl 
Dll 
Dm 
Div 
Aal 
Aa2 
Abl 
Ab2 
Bal 
Ba2 
Bbl 
Bb2 
Cal 
Ca2 
Cbl 
Cb2 
Di 
Dn 
Dill 
Div 
Aal 
Aa2 
Abl 
A  b2 
Bal 
Ba2 
Bbl 
Bb2 
Cal 
Ca2 
Cbl 
Cb2 
Di 
Dn 
Din 
Div 
Aal 

Abl 
Ab2 
Bal 
Ba2 
Bbl 
B1.2 
Cal 
Ca2 
Cbl 
Cb2 
Di 
Dn 
Din 
Div 
Aal 
Aa2 
Abl 
Ab2 
Bal 
Ba2 
Bbl 
Bb2 
Cal 

Windsor 

17 
18 
*13 
20 

21 

22 
20 
18 
20 
23 
18 
11 
11 
8 

3 
4 
2 
0 
2 
1 
0 
2 
2 
2 
0 
2 
1 
0 
0 
40 
0 
0 
0 
0 

1 

0 
0 

1 
1 

4 
1 

0 

1 
0 
0 
62 
11 
9 
5 
4 
8 
G 
8 
7 
12 
11 
7 
7 
0 
2 
1 
71 
6 
6 
5 
7 
6 
0 
6 
5 
5 
5 
5 

1 
0 
0 
80 
16 
15 
15 
17 
15 
16 
15 
17 
16 

Mazzard  

do                             

do  

do 

Yellow  Spanish  

do 

do    

do 

Montmorency       

do 

do      

do 

do             

Not  budded 

Windsor  

28 
:u) 
''7 

do  

do 

do  

25 

29 
29 
31 
31 
27 
23 
29 
29 

-do  .. 

do 

do                 

Montmorency  

do                          

do 

do                          -     --- 

Windsor  

14 
15 
15 

Yellow  Spanish 

Early  Prolific       

14 
20 
21 
19 
17 
24 
18 
16 
13 
17 
18 
18 
13 
13 
14 

do                 

do 

Purple  1C  o'g       

do 

do                                      

do 

Italian  Prune 

do 

do                            .... 

do          

Early  Prolific                  

Purple  E"-»-           

Not  budded 

Early  Prolific 

17 
22 
20 
15 
19 
27 
17 
22 
22 
25 
24 
23 
13 
14 
14 

'do     

..  do  

do               

do     °°       

do 

do                    

do                           .  ... 

do        

do 

Early  Prolific     

Purule  E<rff 

Purple  E  <»•<>•  t  

Not  budded                     

15 
15 

do 

do     

15 
15 
14 
14 
15 
15 

do 

do 

do          

do 

Flemish  Beantv... 

*Five  buds  of  the  Montmorency  were  inserted  by  mistake  of  the  buddor. 
t  Should  have  been  Felleuburg—  mistake  of  budder. 


261 


TABLE  11. — Showing  the  number  of  budded  stocks  in  each  treated  and  untreated  section  - 

Continued. 


lioW. 

Kind  of  stock. 

Section. 

Variety  of  bud. 

Number 
budded. 

dumber 
left  im- 
budded. 

Ca2 

Flemish  Beauty  

15 

14 

Cbl 

do 

15 

16 

Cb2 

do              

15 

•      0 

15 

0 

14 

1 

do* 

15 

0 

Not  budded                      .  - 

97 

VT 

T)r 

Duchess  .     .        

58 

3 

HIT 

59 

2 

"HlIT 

Flemish  Beauty      

58 

2 

Not  budded 

251 

VII 

F         1 

Cal 

Flemish  Beauty  

59 

51 

do 

64 

59 

Phi 

do                          -   ... 

59 

55 

Ph9 

do 

62 

69 

VTTT 

F         1 

B'll 

Anjou  

63 

62 

j?  rencu  pear  ........ 

15  a2 

do                      

61 

63 

Klil 

do 

59 

63 

Jlli"' 

do                   

61 

60 

T~5T 

T 

Ail 

15 

9 

A  a9 

do 

11 

11 

Ahl 

do            

14    . 

13 

Ab2 

do 

12 

8 

Bal 

14 

7 

J{a9 

do 

12 

12 

Bbl 

do                       ... 

13 

9 

Bl>2 

do            

14 

9 

Cal 

16 

8 

C^2 

do                      ........ 

17 

11 

Cbl 

do 

13 

13 

Cb2 

do 

12 

13 

Di 

Duchess        

11 

0 

Dil 

13 

0 

Dill 

Flemish  Beauty          

14 

0 

DiV 

62 

x 

Di 

29 

3 

DII 

28 

5 

Dm 

33 

2 

DiV 

Not  budded 

202 

XI 

Cal 

71 

10 

Ca2 

do             .            ...... 

58 

11 

Cbl 

do     

57 

10 

Cb2 

do 

70 

11 

XII 

American  pear  ....... 

Bal 

56 

13 

Ba2 

do 

58 

8 

Bbl 

do 

49 

10 

Bb2 

do               

63 

17 

XIII 

Aal 

64 

21 

Aa2 

do                        

38 

33 

Abl 

do 

39 

16 

Ab2 

do 

47 

14 

XIV 
XV 
XVI 

American  apple  t  
American  apple  t  
French  apple  t      .... 

XVII 

French  applet  

XVIII 

French    apple    aeed- 
linu-st    

XIX 
XX 
XXI 

French  pear  seed  t.  -  . 
Peach  seedlings  t  

Aal 

53 

39 

Aa2 

do 

46 

37 

Abl 

do                          

31 

48 

Ab2 

do          

27 

57 

*  Should  have  been  Flemish  Beauty — mistake  of  budder. 

t  As  no  disease  appeared  in  the  apple  buds  data  is  not  valuable.  Apple  seedlings  were  not  budded; 
peach  showed  uo  disease;  none  of  pear  seed  germinated. 

Soil,  stocks,  and  buds. — The  soil  upon  which  the  nursery  was  planted  is  considered 
hy  practical  nurserymen  as  well  suited  to  the  growing  of  plums  and  cherries  but  as 
lacking  somewhat  in  the  qualities  which  go  to  make  up  the  best  soil  for  pears  and 
apples,  being  of  insufficient  depth  and  a  trifle  too  light.  Immediately  previous  to 
the  experiment  the  soil  had  been  planted  to  corn,  but  what  fertilizers  had  been 
used,  if  any,  and  what  crops  were  grown  anterior  to  that  season,  I  have  not  been 
able  to  ascertain.  No  fertilizer  was  applied  before  putting  in  the  stocks  and  the 


262 

only  treatment  the  soil  received  was  a  dressing  in  November  and  December  of  1891 ,  of 
33  wagon  loads  of  well-rotted  barnyard  manure  from  the  station  manure  platform, 
evenly  distributed  between  the  rows. 

The  stocks  were  furnished  by  various  nursery  firms  as  stated  in  a  previous  article,* 
and  the  different  lots  were  of  apparently  equal  vigor — lirst  grade  with  the  exception 
of  American  pear  stocks,  which  owing  to  the  lateness  of  the  season  were  third  grade. 
In  the  planting  which  was  done  between  the  dates  of  April  27  and  May  3,  care  was 
taken  that  each  stock  was  firmly  pressed  into  the  soil.  Stocks  of  the  same  kind  from 
different  nursery  firms  were  thoroughly  mixed  together.  In  all  respects  the  normal 
nursery  methods  were  followed  out  as  nearly  as  possible.  The  budding  was  done  -u 
the  dates  above  recorded  by  two  experienced  budders  employed  by  the  Station.  Tie 
scions  for  cherry,  pear,  and  apple  buds  were  cut  from  trees  growing  in  the  nursery 
rowst  of  Selover  and  Atwood.  Plum  scions  were  furnished  by  Maxwell  &  Bron., 
from  their  bearing  orchard. 

Treatment  with  fungicides. — Only  the  two  well-known  fungicides,  ammoniacal  ao- 
lutiouof  copper  carbonate  and  Bordeaux  mixture  were  used.  The  formulae  used  in 
1891  were  those  in  common  use  throughout  America.  The  Bordeaux  mixture  was 
diluted  in  the  treatments  for  1892  and  prepared  after  the  manner  first  proposed  by 
Dr.  G.  Patrigeon.t 

The  formulae  are  given  below : 

Ammoniacal  solution  of  copper  carbonate,  formula  used  in  1891. 

Five  ounces  of  cupric  basic  carbonate  (copper  carbonate)  dissolved  in  ammonia 
(3  to  4  pints  of  26  °)  and  added  to  50  gallons  of  water.  Care  was  taken  that  all  the 
carbonate  was  dissolved  in  the  ammonia,  enough  being  added  for  the  solution. 

Ammoniacal  solution  of  copper  carbonate,  formula  used  in  1892. 

Identical  with  the  above  in  strength.  The  carbonate  was  wetted  with  one  pint  of 
water,  previous  to  adding  the  ammonia,  to  facilitate  the  solution. 

Bordeaux  mixture,  formula  used  in  1891. 

Six  pounds  of  cupric  sulphate  (copper  sulphate  or  blnestone)  dissolved  in  12  gal- 
lons of  water.  Four  pounds  of  stone  lime  slaked  in  a  small  quantity  of  water  and 
made  up  to  3  or  4  gallons  of  thin  milk.  The  lime  was  added  slowly  to  the  cupric 
sulphate  and  the  whole  made  up  to  22  gallons. 

Bordeaux  mixture,  formula  used  in  1892. 

Two  pounds  cupric  sulphate  dissolved  in  15  gallons  of  water.  Two  pounds  Rhode 
Island  stone  lime  slaked  in  small  quantity  of  water  and  made  up  to  5  gallons. 
The  lime  was  added  slowly  to  the  cupric  sulphate,  testing  the  mixture  frequently 
during  the  addition  with  a  few  drops  of  a  concentrated  solution  of  potassium  fer- 
rocyanide  (yellow  prussiate  of  potash)  and  ceasing  the  addition  of  the  lime  when 
no  red  color  was  given  to  the  drops  of  the  ferrocyauide.  For  convenience  this  may 
be  called  a  60- gallon  formula,  as  it  requires  that  amount  of  water  to  contain  as 
much  copper  sulphate  as  the  standard  strength,  viz,  6  pounds. 

*  Bull  No.  3,  Div.  Veg.  Path.,  p.  57. 

t  A  practice  much  in  vogue  among  nurserymen,  but  certainly  not  founded  upon  a 
knowledge  of  the  laws  governing  bud  variation.  The  selection  of  buds  from  indi- 
vidual bearing  trees  of  known  vigor  and  productiveness  is  insisted  upon  by  the  best 
cultivators. 

tPatrigeon,  G.  Revue  Viticole,  <Jour.  d'  Agric.  Pratique,  1890,  t.  I.  54e  anue'e, 
p.  701. 


263 

The  treatments  were  begun  in  1801  about  three  weeks  after  planting,  when  the 
first  leaves  were  nearly  three-fourths  grown.  The  dates  upon  which  the  applications 
were  made  were  May  21,  June  3,  June  24,  July  9,  July  24,  August  8,  and  August  28. 
As  indicated  above  in  the  plan,  half  of  each  section  was  treated  three  times.  Those 
treated  three  times  were  sprayed  on  the  first  three  dates  mentioned. 

In  1892  the  treatments  were  begun  on  May  26,  when  the  leaves  had  attained  full 
size,  and  the  first  appearance  of  the  disease  was  observed.  The  dates  of  treatment 
are  May  26-27,  June  15-16,  June  23,  July  6-7,  July  21,  and  August  5.  In  order  to 
apply  the  mixture  more  thoroughly  the  spray  was  passed  rapidly  over  the  plants 
and, the  operation  repeated  after  the  first  spraying  had  dried.*  This  method  insured 
as  near  a  complete  coating  of  the  fungicide  as  possible,  and  it  was  found  that-  the 
Bordeaux  mixture  of  this  weak  strength  adhered  with  remarkable  tenacity,  being 
plainly  visible  twelve  weeks  after  application. t  Care  was  taken  to  spray  the  under 
side  of  the  leaves  on  the  cherry  and  plum  stocks,  but  pear,  quince,  and  apple 
stocks  were  sprayed  from  above. 

The  treatments  *bf  1892  were  not  continued  so  late  in  the  season  as  those  of  1891, 
and  the  different  sections  received  respectively  five  and  six  sprayings,  instead  of  three 
and  six  as  in  1891.  Those  receiving  five  sprayings  were  treated  on  the  first  five  dates 
mentioned  above.  The  actual  amount  of  the  fungicides  used  will^be  of  little  value  in 
estimating  the  quantities  that  will  be  necessary  in  treatments  on  a  large  scale,  but 
for  the  convenience  of  other  experimenters  it  may  be  roughly  estimated  to  equal  3£ 
to  4|  gallons  of  solution  per  1,000  one-year-old  stocks  and  proportionately  more 
for  budded  stocks.  By  one-year-old  stocks  is  meant  stocks  previous  to  budding. 

The  spraying  was  done  with  a  W.  &  B.  Douglass  " Perfection"  knapsack  sprayer, 
which  proved  moderately  satisfactory,  although  a  hand-wheel  machine  would  un- 
doubtedly have  been  better. 

DESCRIPTION  OF  PLATES.* 

PLATE  XXI.  French  pear  stocks,  planted  in  1891  and  treated  7  times  with  Bor- 
deaux mixture,  full  strength;  left  unbudded  in  the  fall  and 
treated  6  times  with  Bordeaux,  one-third  strength,  in  1892. 
These  could  properly  be  called  3-year-old  seedlings.  Situation 
of  stocks,  Row  VIII,  east  end. 

XXII.  French  pear  stocks,  similar  to  those  in  Plate  xxi,  but  without 
treatment  either  in  1891  or  1892.  Situation  of  stocks,  Row  VI, 
east  end.  Showing  defoliation  caused  by  Entomosporium. 

XXIII.  French  pear  stocks,  similar  to  those  in  Plate  xxi,  but  treated  7 

times  in  1891  and  6  times  in  1892  with  ammoniacal  solution. 
.  Situation  of  stocks,  Row  VIII,  near  center. 

XXIV.  Angers  quince  stocks,  planted  as  cuttings  in  1891  and  treated  7 

times  with  Bordeaux  full  strength  the  first  season,  left  un- 
budded in  the  fall,  and  treated  6  times  with  Bordeaux  one-third 
strength  in  1892.  These  could  properly  be  called  3-year-old 
cuttings.  Situation,  Row  V,  near  east  end. 

XXV.  Angers  quince  stocks,  similar  to  those  in  Plate  xxiv,  but  without 
treatment  either  in  1891  or  1892.  Situation,  Row  V,  east  end, 
one  rod  east  of  those  in  Plate  xxiv.  Showing  defoliation  by 
Entomosporium. 

*  Suggested  first  by  N.  A.  Cobb,  Dialogue  concerning  the  manner  in  which  a  poison- 
ous sfmiy  does  its  work  in  preventing  or  checking  blight.  ^Agricultural  Gazette 
N.  S.  Wales,  Vol.  n,  pp.  779-786. 

t  These  double  sprayings  were  made  on  the  first,  fourth,  fifth,  and  sixth  treatments 
only. 

t  All  plates  are  reproduced  from  photographs  taken  8  feet  from  the  stocks  on  Sep- 
tember 29  and  October  11. 


264 

PLATE  XXVI.  Windsor  "buds,"  on  Ma haleb.  The  Mahal eb  stocks  were  treated 
7  times  in  1891  with  Bordeaux  mixture  and  the  "buds"  were 
treated  6  times  in  1892  with  Bordeaux  one-third  strength.  Sit- 
uation, Kow  I,  near  west  end. 

XXVII.  Windsor  "buds,"  on  Mahal eb.  Similar  to  those  in  Plate  xxvi, 
but  untreated  both  in  1891  and  1892.  Situation,  Row  I,  near 
east  end,  showing  defoliation  by  Cylindrosporium. 

XXVIII.  Early  Prolific  "buds,"  on  Myrobolan.  The  Myrobolan  stocks 
were  treated  7  times  in  3891  with  Bordeaux  and  the  "buds" 
were  treated  6  times  with  Bordeaux  one-third  strength  in  1892. 
Situation,  Row  III,  west  end. 

XXIX.  Early  Prolific  "buds,"  on  Marianna.  Similar  to  those  in  Plute 
xxvni,  but  untreated  both  in  1891  and  1892.  (The  difference 
of  stocks  upon  which  budding  was  done  made  no  difference 
as  regards  the  leaf-blight;  hence  the  fact  that  the  "buds"  in 
Plate  xxvni  were  on  Myrobolan  stocks  and  in  Plate  x:ox 
•were  on  Marianna  does  not  affect  the  comparison.)  Situation, 
Kow  IV,  east  end. 


JOURNAL  OF  MYCOLOGY,  U.  S.  DEPARTMENT  OF  AGRICULTURE.  VOL.    VII,  PLATE  XXI. 


JOURNAL  OF  MYCOLOGY,  U.  S.  DEPARTMENT  OF  AGRICULTURE.  VOL.  VII,  PLATE  XXII 


, 


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JOURNAL  OF  MYCOLOGY,  U.  S.  DEPARTMENT  OF  AGRICULTURE.         VOL.  VII,  PLATE  XXIV. 


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JOURNAL  OF  MYCOLOGY,  U.  S.  DEPARTMENT  OF  AGRICULTURE.  VOL.  VII,  PLATE  XXV. 


JOURNAL  OF  MYCOLOGY,  U.  S.  DEPARTMENT  OF  AGRICULTURE.      VOL.  VII,  PLATE  XXVI. 


CHERRY  LEAF-BLIGHT. 
Windsor  buds  on  Mahaleb  stocks.      Treated  with  Bordeaux  mixture.      (Fairchild.) 


JOURNAL  OF  MYCOLOGY,  U.  S.  DEPARTMENT  OF  AGRICULTURE.      VOL.  VII,  PLATE  XXVII. 


CHERRY  LEAF-BLIGHT. 
Windsor  buds  on  Mahaleb  stocks.      Untreated.      (Fairchild.) 


JOURNAL  CF  MYCOLOGY,  U.  S.  DEPARTMENT'OF  AGRICULTURE.      VOL.  VII,  PLATE  XXVIII. 


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JOURNAL  OF  MYCOLOGY,  U.  S.  DEPARTMENT  OF  AGRICULTURE.          VOL.  VII,  PLATE  XXIX. 


U.C.  BERKELEY  LIBRARIES 


